Backsprings breaking on my folders?? Picture for comments please!

[Redrummd]

I bought a dozen knife blanks for my custom stonework scales.... I have had three backsprings break and I would like to know why they are breaking. So here is a picture of one of the three.... The supplier is replacing them but I am concerned about one breaking after I ship a knife to a customer.

 

[kc custom]

I used to have that problem, And I do my own heat treat so it was really a concern.Lo and behold after Rc checking one I was almost as hard with my springs as people do bladesRc58 now I draw them to 48ish and haven't had a problem for a few years. I pray I've got most of those early ones redone.Guess its called paying your dues or a learning curve, not fun on slippies.

 

[mete]

I'd like to see details on the fracture surface .It looks like fracture of new springs rather than a fatigue failure. That would usually mean improper HT.Make sure that there are no scratches to start a failure .What are the specs ,steel type and hardness of the springs ?

 

[Bruce Bump]

You need to give us more details. From here I think I can see coarse grain which relates to improper heat treating.

 

[Don Hanson III]

Low (bad) quality product, look else where or make your own.